Drinking one or two daily sugar-sweetened beverages can lead to excess weightgain and a greater risk of developing type 2 diabetes and cardiovascular disease, according to a new study by researchers at Harvard T.H. Chan School of Public Health. In the most comprehensive review of the evidence on the health effects of sugar-sweetened beverages to date, the researchers also took a closer look at the unique role that the sweetener fructose may play in the development of these conditions.

The paper was published online September 30, 2015 in the Journal of theAmerican College of Cardiology.

Fructose is metabolized in the liver where it can be converted to fatty compounds called triglycerides, which may lead to fatty liver disease and insulin resistance, a key risk factor for developing diabetes and cardiovascular disease. The major source of fructose in the diet comes from fructose-containing sugars—sucrose and high fructose corn syrup—found in sugar-sweetened beverages, according to the researchers.

In the new paper, which reviewed recent epidemiological studies and meta-analyses of these studies, the researchers found that people who consumed one or two sugary drinks a day had a 35% increase in risk for heart attack or fatal heart disease, a 16% increase in risk for stroke, and a 26% increased risk for developing type 2 diabetes, when compared with people who drank fewer sugar-sweetened beverages.

“Our findings underscore the urgent need for public health strategies that reduce the consumption of these drinks,” said Frank Hu, professor of nutrition and epidemiology and lead author of the paper. Research scientist Vasanti Malik co-authored the study.